Insig tot Loodpartikels in Wild / Insight to Lead Particles in game animals

X-strale van loodfragmente / X-ray of lead fragments

X-strale van ʼn jakkals en ‘n rooibok wys dat loodkoeëls in honderde klein fragmente kan opbreek binne in die dier wat geskiet is. Loodfragmente is meer as 30 cm van die wondkanaal gevind. Die uitbeelding aan die regterkant is van veerwild waarvan SA Jagters se bestuurder jagsake gedink het nie loodkorrels bevat nie. Dit het egter lood bevat. Die nanopartikels is só klein dat dit nie met die blote oog sigbaar is nie. Hierdie partikels is veral problematies en word direk deur die selwande opgeneem.

X-ray images of a jackal and a impala show that lead bullets can break into hundreds of small fragments inside the body of the animal that has been shot. Lead fragments were found more than 30 cm away from the wound channel. The image on the right is of game birds that SA Hunters’ manager for hunting affairs thought did not contain lead pellets. However, they did contain lead. The nanoparticles are so small that they are not visible to the naked eye. These particles are particularly problematic and are directly absorbed by cell walls.

Loodammunisie en voëls

Bloedloodvlakke in aasvoëls / Blood lead levels in vultures

Verskeie aasvoëlpopulasies in Suid Afrika het hoë bloedloodvlakke / Several vulture populations in South Africa have elevated blood lead levels.

Bron: Resultate van navorsing. Lead levels in South Africa’s Gyps vultures. 2020.  Linda van den Heever, Hanneline Smit-Robinson, Vinny Naidoo, Andrew E. McKechnie. Webinar of Birdlife SA.

Wetenskaplike artikel: Blood and bone lead levels in South Africa’s Gyps vultures: Risk to nest-bound chicks and comparison with other avian taxa. van den Heever L, Smit-Robinson HA, Naidoo V et al .2019. Sci Total Environ 669:471–480

Loodammunisie en aasvoëls / Lead ammunition and vultures

Loodammunisie is geïdentifiseer as een van die belangrikste bronne van hoë bloedloodvlakke in ‘n aasvoëlkolonie by Dronfield Natuurreservaat.
Lead ammunition has been identified as one of the most important sources of high blood lead levels in a vulture colony at Dronfield Nature Reserve.

Scientific article: Identifying the origin of lead poisoning in white‑backed vulture (Gypsafricanus) chicks at an important South African breeding colony: a stable lead isotope approach. Linda van den Heever, Marlina A. Elburg, Linda Laccheri, Vinny Naidoo, Henriette Ueckermann, Grant Bybee,  Hanneline A. Smit‑Robinson,  Melissa A. Whitecross, Andrew E. McKechnie. 2022. Environmental Science and Pollution Research. https://doi.org/10.1007/s11356-022-23209-z

Loodsinkers en krokodille / Lead sinkers and crocodiles

‘n Onlangse studie deur navorsers van die Universiteit van die Witwatersrand (WITS), Universiteit van Pretoria (UP), Nasionale Dieretuin en die Tshwane Universiteit van Tegnologie (TUT) het bevind dat lood (Pb) teenwoordig was in bloedmonsters van al 22 wilde krokodille wat hulle ondersoek het, met konsentrasies wat wissel van 86 tot 13 100 nanogram (ng) lood per ml bloed (ng/ml). Loodvergiftiging was beduidend hoër by manlike diere (gemiddelde bloedloodkonsentrasie van 3 780 ng/ml) in vergelyking met vroulike diere (gemiddeld 266 ng/ml). Verskeie krokodille het duidelike kliniese bewyse van Pb-vergiftiging getoon, en die hoogste bloedloodkonsentrasie (13 100 ng/ml) was nie net die hoogste ooit aangeteken tydens ‘n studie van wilde krokodille (krokodille, alligators, kaaimanne en ghariale) nie, maar ook vir alle gewerwelde diere. Krokodille wat oor ʼn langtermyn aan lood blootgestel word, kan bloedarmoede ontwikkel en die toestand van hulle tande kan só ernstig verswak dat nuwe tande nie kan vorm nie. Die diere vrek uiteindelik weens wanvoeding. Hierdie simptome stem ooreen met loodvergiftiging wat by voëls en soogdiere waargeneem is, maar nog nie voorheen by krokodille aangeteken is nie.

Bron: Loodsinkers vergiftig Nyl-krokodille in St. Lucia-meergebied, in SA Jagter, deur  Xander Combrink en Marc Humphries.

A recent study by researchers from the University of the Witwatersrand (WITS), University of Pretoria (UP), National Zoo, and Tshwane University of Technology (TUT) found that lead (Pb) was present in blood samples of all 22 wild crocodiles they examined, with concentrations ranging from 86 to 13,100 nanograms (ng) of lead per millilitre of blood (ng/ml). Lead poisoning was significantly higher in male animals (average blood lead concentration of 3,780 ng/ml) compared to female animals (average 266 ng/ml). Several crocodiles showed clear clinical evidence of Pb poisoning, and the highest blood lead concentration (13,100 ng/ml) was not only the highest ever recorded in a study of wild crocodiles (crocodiles, alligators, caimans, and gharials) but also for all vertebrate animals. Crocodiles exposed to lead over a long period can develop anaemia, and the condition of their teeth can be so severely compromised that new teeth cannot form. The animals ultimately die of malnutrition. These symptoms resemble lead poisoning observed in birds and mammals but have not been previously documented in crocodiles.

Source: Lead sinkers poison Nile crocodiles in St. Lucia Lake area, in SA Hunter, by Xander Combrink and Marc Humphries

Scientific article: High lead exposure and clinical signs of toxicosis in wild Nile crocodiles (Crocodylus niloticus) from a World Heritage site: Lake St Lucia estuarine system, South Africa. 2022. Marc Humphries, Jan Myburgh, Robert Campbell and Xander Combrink. by https://doi.org/10.1016/j.chemosphere.2022.134977